现代通信网主要由交换网、传输网和接入网三大部分组成。随着“铁路通信三年攻坚战”的实施，铁路通信主干网络的功能越来越强，但是作为整个铁路通信网组成之一的用户接入系统却因技术装备上的相对落后而成为铁路通信事业发展的“瓶颈”。本文即对接入网（AN）在铁路通信网中的实现作若干探讨。 Modern communication network mainly consists of switching network, transmission network and access network composed of three parts. With the implementation of the “three years of railway communication”, the backbone network of railway communications has become more and more powerful. However, as a component of the entire railway communication network, the user access system has become a railroad due to the relative backwardness of technology and equipment Communication development “bottleneck ”. This article is about the access network (AN) in the railway communication network to achieve some discussion.